GE alternative and outcome Beniamino Di Girolamo 2nd LESS Collaboration Steering Committee – 3 November 2018

Design basic facts GE Inspection Robotics is a specialized company in robotics It is a joint venture with ETH Zurich and it was a spin-off company of ETH The design is based on the inchworm concept where during the treatment the main body of the robot stays still and a motor performs the very precise steps for the helix of treatment over 2 cm at the time When the complete 2 cm are done, the central part of the body is clamping and the main body released. The same motor moves the main body to the next position (macro-step), clamps and the treatment starts again B. Di Girolamo - GE alternative - 03/11/2017

Design basic facts B. Di Girolamo - GE alternative - 03/11/2017

Design basic facts carriage electronics box (E-Box) AC 24V 100-230V AC optical fibre Ethernet robot position laser enable laser ON carriage electronics box (E-Box) AC 24V robot control umbilical, 5...18m 24V DC 100-230V AC valves N2 flow N2 (3...8 bar) pneumatics box (P-Box) pressure (6 bar) 3x PP tubes B. Di Girolamo - GE alternative - 03/11/2017

What we get from the company A fully tested and commissioned carriage ready for the integration with the optics The carriage is based on only two motors and clamps The translation without gears to have zero-backlash The rotation with a pre-loaded gear to eliminate backlash A pneumatic-clamping system The low level control system The pneumatic box We will participate to commissioning to expedite the hand-over B. Di Girolamo - GE alternative - 03/11/2017

Remaining risks and mitigations Consequence Implemented mitigation Risk Level Poss. Mitigation Traction not sufficient Robot slips  inaccurate pattern limit and monitor motor force; large clamping force moderate check w/ prototype additional slip sensor Disturbance from stepping too large small disturbed zone on laser pattern every 20mm active compensation in SW Centering of fibre inaccurate laser focus not on ideal circle, but inclined adjustment screws for fibre head; fix orientation of fibre head low Centering of robot in BS inaccurate changing focal distance, inclination of pattern system failure during operation writing process connot be completed have spare system – implicit with different sizes disturbance of / friction from umbilical too large slip or uncontrolled decentering of robot decouple umbilical from scanning slider/head acitive, controlled umbilicial retraction, umbilical on low-friction sliders play in robot to large inaccurate pattern, double perforations B. Di Girolamo - GE alternative - 03/11/2017

Milestones and deliverables Date Start Principal approach fixed 2017-08-01 2017-08-07 LESS Concept Released Concept description w/ more detailed design, inkl. mechanics, control, user interface Interfaces w/ CERN defined Risk assessment  Concept release 2017-08-31 2017-09-09 LESS Design Released Detailed Design (Mech., Electr.) SW Architecture Optics integration fixed  Feature Freeze  Release Design 2017-10 2017-10-20 Prototype production Documents Long lead items ordered  Release for manufacturing 2017-11 2017-11-10 Prototype built Prototype running and lab tested  System ready to hand over 2018-01 System Verified System commissioned, basic tests run at CERN Performance verified Review 2018-02 B. Di Girolamo - GE alternative - 03/11/2017

Planning Schedule is tight however the company started the final drawings production after the review to be able to finally deliver to us the carriage ready to use by ~ January 26th The participation to the commissioning will shorten the integration with the higher level control and synch with laser done by Dundee Caveat: the dimension of the fibre head needs to be reduced to allow enough excursions for the clamps. The fibre has to soon go back to the producer B. Di Girolamo - GE alternative - 03/11/2017

The review report is attached to the agenda Outcome of the review The outcome is positive and the reviewers indicated the points to consider The carriage proposed by GE Inspection Robotics is an industrialized item and will enable us to meet the deadline for the preparation of a beam screen by end February 2018 as well as to arrive to the HL-LHC International Review for the e-cloud suppression with a treated racetrack LHC beam screen The review report is attached to the agenda B. Di Girolamo - GE alternative - 03/11/2017

Proposal We adopt this solution to meet the 7 mm precision in translation and to be able to produce in February an automatically treated beam screen We can optionally procure a second carriage for redundancy to reduce the risks and to be able to independently work on it in parallel in case any problem would arise during the treatment in Dundee. The cost is very reasonable B. Di Girolamo - GE alternative - 03/11/2017